跑台运动对切除卵巢大鼠骨质疏松症的保护机制

The protective mechanism of treadmill exercise on osteoporosis in ovariectomized rats

目的由Hedgehog-Gli信号通路探讨跑台运动对卵巢切除所致骨质疏松症大鼠的保护机制。方法50只雌性SD大鼠,随机分为假手术组(S,15)、造模组(Z,35)。假手术组仅切除卵巢周围的少量脂肪,造模组切除双侧卵巢。术后10周采用苏木精-伊红染色法验证造模。将成功造模的大鼠随机分为模型组(M)、戊酸雌二醇阳性对照组(P)和跑台运动组(E),每组各10只。P组以0.184 mg/(kg·d)的标准灌服戊酸雌二醇混悬液,其他组灌服等剂量生理盐水,每日一次,E组同时进行每周5 d,每次30 min的中等强度跑台训练,干预12周后取材,检测血清抗酒石酸酸性磷酸酶(TRACP)、Ⅰ型前胶原N端肽(PINP)、Ⅰ型胶原交联C-末端肽(CTX)和骨钙素(OC)的水平,Micro-CT检测骨密度,强度仪上检测骨力学性能,Western blot检测股骨中Shh、Ptc、Smo及Gli蛋白表达水平。结果与S组相比,M组骨形成代谢指标、骨密度值、骨力学性能和股骨Shh、Ptc、Smo及Gli蛋白表达均下降(P<0.01);与M组相比,P组和E组骨形成代谢指标、骨密度值、骨力学性能和股骨Shh、Ptc、Smo及Gli蛋白表达均上升(P<0.01);与P组相比,E组股骨Shh、Ptc、Smo及Gli蛋白表达升高(P<0.05)。结论12周跑台运动可通过上调股骨Shh、Ptc、Smo及Gli的表达介导对去卵巢大鼠骨代谢的调节,改善骨质疏松症。

Objective To explore the protective mechanism of treadmill exercise on ovariectomized osteoporosis rats through Hedgehog-Gli signaling pathway.Methods 50 female SD rats were randomly divided into sham operation group(S,15)and model group(Z,35).The sham group removed only a small amount of fat around the ovaries,while the model group removed both ovaries.The model was verified by hematoxylin-eosin staining 10 weeks after operation.The successful rats were randomly divided into model group(M),positive control group(P)and treadmill exercise group(E),with 10 rats in each group.Group P was given 0.184 mg/(kg d)estradiol valerate suspension,while the other groups were given the same dose of normal saline once a day.Group E was also given moderate-intensity treadmill training for 30 min minutes,five days a week.After 12 weeks of intervention,blood samples were collected,and the serum levels of procollagen type I N-terminal peptide(PINP),tartrate-resistant acid phosphatase(TRACP),collagen type I cross-linked C-terminal peptide(CTX)and osteocalcin(OC)were detected.Bone mineral density was detected by Micro-CT,bone mechanical properties were detected by material machine,and the expression of Shh,Ptc,Smo and Gli proteins in femur were detected by Western blot.Results Compared with S group,the indexes of bone formation and metabolism,bone mineral density,bone mechanical properties and the expressions of Shh,Ptc,Smo and Gli in femur in group M decreased(P<0.01).Compared with M group,the indexes of bone formation and metabolism,bone mineral density,bone mechanical properties and the expressions of Shh,Ptc,Smo and Gli in f femur in group M decreased(P<0.01).Compared with P group,the expressions of Shh,Ptc,Smo and Gli in femur in group E were higher(P<0.05).Conclusion 12 weeks treadmill exercise may mediate the regulation of bone metabolism in ovariectomized rats by up-regulating the expressions of Shh,Ptc,Smo and Gli,and improve osteoporosis.